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            <div><h3 class="title">
                <a name="asio.reference.IteratorConnectToken"></a><a class="link" href="IteratorConnectToken.html"
                                                                     title="Iterator connect token requirements">Iterator
                connect
                token requirements</a>
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    <p>
        An iterator connect token is a <a class="link" href="../overview/model/completion_tokens.html"
                                          title="Completion Tokens">completion
        token</a> for completion signature <code class="computeroutput"><span class="keyword">void</span><span
            class="special">(</span><span class="identifier">error_code</span><span class="special">,</span> <span
            class="identifier">Iterator</span><span class="special">)</span></code>, where the type <code
            class="computeroutput"><span class="identifier">Iterator</span></code>
        is used in the corresponding <code class="computeroutput"><span class="identifier">async_connect</span><span
            class="special">()</span></code> function.
    </p>
    <h5>
        <a name="asio.reference.IteratorConnectToken.h0"></a>
        <span><a name="asio.reference.IteratorConnectToken.examples"></a></span><a class="link"
                                                                                   href="IteratorConnectToken.html#asio.reference.IteratorConnectToken.examples">Examples</a>
    </h5>
    <p>
        A free function as an iterator connect token:
    </p>
    <pre class="programlisting"><span class="keyword">void</span> <span class="identifier">connect_handler</span><span
            class="special">(</span>
    <span class="keyword">const</span> <span class="identifier">asio</span><span class="special">::</span><span
                class="identifier">error_code</span><span class="special">&amp;</span> <span
                class="identifier">ec</span><span class="special">,</span>
    <span class="identifier">asio</span><span class="special">::</span><span class="identifier">ip</span><span
                class="special">::</span><span class="identifier">tcp</span><span class="special">::</span><span
                class="identifier">resolver</span><span class="special">::</span><span
                class="identifier">iterator</span> <span class="identifier">iterator</span><span
                class="special">)</span>
<span class="special">{</span>
  <span class="special">...</span>
<span class="special">}</span>
</pre>
    <p>
        An iterator connect token function object:
    </p>
    <pre class="programlisting"><span class="keyword">struct</span> <span class="identifier">connect_handler</span>
<span class="special">{</span>
  <span class="special">...</span>
  <span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">typename</span> <span
                class="identifier">Iterator</span><span class="special">&gt;</span>
  <span class="keyword">void</span> <span class="keyword">operator</span><span class="special">()(</span>
      <span class="keyword">const</span> <span class="identifier">asio</span><span class="special">::</span><span
                class="identifier">error_code</span><span class="special">&amp;</span> <span
                class="identifier">ec</span><span class="special">,</span>
      <span class="identifier">Iterator</span> <span class="identifier">iterator</span><span class="special">)</span>
  <span class="special">{</span>
    <span class="special">...</span>
  <span class="special">}</span>
  <span class="special">...</span>
<span class="special">};</span>
</pre>
    <p>
        A lambda as an iterator connect token:
    </p>
    <pre class="programlisting"><span class="identifier">asio</span><span class="special">::</span><span
            class="identifier">async_connect</span><span class="special">(...,</span>
    <span class="special">[](</span><span class="keyword">const</span> <span class="identifier">asio</span><span
                class="special">::</span><span class="identifier">error_code</span><span
                class="special">&amp;</span> <span class="identifier">ec</span><span class="special">,</span>
      <span class="identifier">asio</span><span class="special">::</span><span class="identifier">ip</span><span
                class="special">::</span><span class="identifier">tcp</span><span class="special">::</span><span
                class="identifier">resolver</span><span class="special">::</span><span
                class="identifier">iterator</span> <span class="identifier">iterator</span><span
                class="special">)</span>
    <span class="special">{</span>
      <span class="special">...</span>
    <span class="special">});</span>
</pre>
    <p>
        A non-static class member function adapted to an iterator connect token using
        <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span
                class="identifier">bind</span><span class="special">()</span></code>:
    </p>
    <pre class="programlisting"><span class="keyword">void</span> <span class="identifier">my_class</span><span
            class="special">::</span><span class="identifier">connect_handler</span><span class="special">(</span>
    <span class="keyword">const</span> <span class="identifier">asio</span><span class="special">::</span><span
                class="identifier">error_code</span><span class="special">&amp;</span> <span
                class="identifier">ec</span><span class="special">,</span>
    <span class="identifier">asio</span><span class="special">::</span><span class="identifier">ip</span><span
                class="special">::</span><span class="identifier">tcp</span><span class="special">::</span><span
                class="identifier">resolver</span><span class="special">::</span><span
                class="identifier">iterator</span> <span class="identifier">iterator</span><span
                class="special">)</span>
<span class="special">{</span>
  <span class="special">...</span>
<span class="special">}</span>
<span class="special">...</span>
<span class="identifier">asio</span><span class="special">::</span><span class="identifier">async_connect</span><span
                class="special">(...,</span>
    <span class="identifier">std</span><span class="special">::</span><span class="identifier">bind</span><span
                class="special">(&amp;</span><span class="identifier">my_class</span><span
                class="special">::</span><span class="identifier">connect_handler</span><span class="special">,</span>
      <span class="keyword">this</span><span class="special">,</span> <span class="identifier">std</span><span
                class="special">::</span><span class="identifier">placeholders</span><span
                class="special">::</span><span class="identifier">_1</span><span class="special">,</span>
      <span class="identifier">std</span><span class="special">::</span><span
                class="identifier">placeholders</span><span class="special">::</span><span
                class="identifier">_2</span><span class="special">));</span>
</pre>
    <p>
        A non-static class member function adapted to an iterator connect token using
        <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span
                class="identifier">bind</span><span class="special">()</span></code>:
    </p>
    <pre class="programlisting"><span class="keyword">void</span> <span class="identifier">my_class</span><span
            class="special">::</span><span class="identifier">connect_handler</span><span class="special">(</span>
    <span class="keyword">const</span> <span class="identifier">asio</span><span class="special">::</span><span
                class="identifier">error_code</span><span class="special">&amp;</span> <span
                class="identifier">ec</span><span class="special">,</span>
    <span class="identifier">asio</span><span class="special">::</span><span class="identifier">ip</span><span
                class="special">::</span><span class="identifier">tcp</span><span class="special">::</span><span
                class="identifier">resolver</span><span class="special">::</span><span
                class="identifier">iterator</span> <span class="identifier">iterator</span><span
                class="special">)</span>
<span class="special">{</span>
  <span class="special">...</span>
<span class="special">}</span>
<span class="special">...</span>
<span class="identifier">asio</span><span class="special">::</span><span class="identifier">async_connect</span><span
                class="special">(...,</span>
    <span class="identifier">boost</span><span class="special">::</span><span class="identifier">bind</span><span
                class="special">(&amp;</span><span class="identifier">my_class</span><span
                class="special">::</span><span class="identifier">connect_handler</span><span class="special">,</span>
      <span class="keyword">this</span><span class="special">,</span> <span class="identifier">asio</span><span
                class="special">::</span><span class="identifier">placeholders</span><span
                class="special">::</span><span class="identifier">error</span><span class="special">,</span>
      <span class="identifier">asio</span><span class="special">::</span><span
                class="identifier">placeholders</span><span class="special">::</span><span
                class="identifier">iterator</span><span class="special">));</span>
</pre>
    <p>
        Using <a class="link" href="use_future.html" title="use_future">use_future</a> as an iterator
        connect token:
    </p>
    <pre class="programlisting"><span class="identifier">std</span><span class="special">::</span><span
            class="identifier">future</span><span class="special">&lt;</span><span class="identifier">asio</span><span
            class="special">::</span><span class="identifier">ip</span><span class="special">::</span><span
            class="identifier">tcp</span><span class="special">::</span><span class="identifier">resolver</span><span
            class="special">::</span><span class="identifier">iterator</span><span class="special">&gt;</span> <span
            class="identifier">f</span> <span class="special">=</span>
  <span class="identifier">asio</span><span class="special">::</span><span class="identifier">async_connect</span><span
                class="special">(...,</span> <span class="identifier">asio</span><span class="special">::</span><span
                class="identifier">use_future</span><span class="special">);</span>
<span class="special">...</span>
<span class="keyword">try</span>
<span class="special">{</span>
  <span class="identifier">asio</span><span class="special">::</span><span class="identifier">ip</span><span
                class="special">::</span><span class="identifier">tcp</span><span class="special">::</span><span
                class="identifier">resolver</span><span class="special">::</span><span
                class="identifier">iterator</span> <span class="identifier">i</span> <span
                class="special">=</span> <span class="identifier">f</span><span class="special">.</span><span
                class="identifier">get</span><span class="special">();</span>
  <span class="special">...</span>
<span class="special">}</span>
<span class="keyword">catch</span> <span class="special">(</span><span class="keyword">const</span> <span
                class="identifier">system_error</span><span class="special">&amp;</span> <span
                class="identifier">e</span><span class="special">)</span>
<span class="special">{</span>
  <span class="special">...</span>
<span class="special">}</span>
</pre>
    <p>
        Using <a class="link" href="use_awaitable.html" title="use_awaitable">use_awaitable</a> as
        an iterator connect token:
    </p>
    <pre class="programlisting"><span class="identifier">asio</span><span class="special">::</span><span
            class="identifier">awaitable</span><span class="special">&lt;</span><span class="keyword">void</span><span
            class="special">&gt;</span> <span class="identifier">my_coroutine</span><span class="special">()</span>
<span class="special">{</span>
  <span class="keyword">try</span>
  <span class="special">{</span>
    <span class="special">...</span>
    <span class="identifier">asio</span><span class="special">::</span><span class="identifier">ip</span><span
                class="special">::</span><span class="identifier">tcp</span><span class="special">::</span><span
                class="identifier">resolver</span><span class="special">::</span><span
                class="identifier">iterator</span> <span class="identifier">i</span> <span class="special">=</span>
      <span class="identifier">co_await</span> <span class="identifier">asio</span><span class="special">::</span><span
                class="identifier">async_connect</span><span class="special">(</span>
          <span class="special">...,</span> <span class="identifier">asio</span><span class="special">::</span><span
                class="identifier">use_awaitable</span><span class="special">);</span>
    <span class="special">...</span>
  <span class="special">}</span>
  <span class="keyword">catch</span> <span class="special">(</span><span class="keyword">const</span> <span
                class="identifier">system_error</span><span class="special">&amp;</span> <span
                class="identifier">e</span><span class="special">)</span>
  <span class="special">{</span>
    <span class="special">...</span>
  <span class="special">}</span>
<span class="special">}</span>
</pre>
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